Variable pitch marine propeller



Sept. 20, 1960 c. A. O'CONNOR 2,953,208

VARIABLE P ITCH MARINE PROPELLER Filed May 15, 1958 ZNVENTOR. CHARLES A. OCONNOF? QTTORNEY.

United States Patent VARIABLE PITCH MARINE PROPELLER Charles A. OConnor, Wantaugh, N.Y., assignor, by direct and mesne assignments, to Lesnor Maehr Marine Co., Inc., Floral Park, N.Y., a corporation of New York Filed May 15, 1958, Ser. No. 735,448

7 Claims. (Cl. 17 0160.24)

This invention relates to propellers and particularly to variable pitch propellers which are used on marine propulsion devices and which may be manually adjusted to improve the operation thereof.

Presently known marine propellers, such as are used on outboard motors and the like have blades which are fixed in relationship to the hub of the propeller assembly. Under certain conditions and a different speeds it is desirable to vary the pitch of the propeller blades to achieve a more favorable result.

Accordingly, it is an object of the present invention to provide a propeller for a marine propulsion device which may be varied to suit the need of the user.

Another object of the present invention is to provide a variable pitch propeller which may be easily substituted for the presently used propellers on outboard motors and the like.

A further object of the present invention is to provide a variable pitch propeller in which the blade variation may be brought about without the use of tools or by a time consuming operation.

Still another object of the present invention is to provide a variable pitch propeller which will maintain its setting despite the vibration and thrust of the blades in their passage through the water.

An object of the present invention is to provide a variable pitch marine propeller which will be durable and troublefree in its operation.

A feature of the present invention is its use of a control ring for guiding the trailing edge of the propeller blades.

Another feature of the present invention is its simplified hub and blade assembly.

Still another feature of the present invention is its use of brake blocks to prevent the blade control ring from shifting out of its set position.

The invention consists of the construction, combination and arrangement of parts, as herein illustrated, described and claimed.

In the accompanying drawing, forming a part hereof is illustrated one form of embodiment of the invention and in which:

Figure l is a view in side elevation of a complete embodiment of the present invention with the propeller hub nut shown in dotted lines.

Figure 2 is a view in rear elevation of the propeller shown in Figure 1 somewhat reduced in scale, with the nut member removed.

Figure 3 is a longitudinal section taken on line 3-3 of Figure 2.

Figure 4 is a view in front elevation of the propeller on a somewhat reduced scale with the blade retaining ring removed, to show the manner in which the blades are held in the hub.

Referring to Figure 1 it will be seen that the propeller member consists of a hub 10, a retaining ring 11, on one end of the hub and a control ring 12 on the opposite end thereof. Propeller blades 13 are pivotally secured to 2,953,208 Patented Sept. 20, 1960 ice ' the hub 10 and retaining ring 11 as shown in Figure 3.

Each blade 13 is provided with a pivot shaft 14 which extends from that portion of the base thereof which is near the leading edge of the blade. A guide detent depends from the base of the blades trailing edge.

Each guide detent 15 rides within an identical helical groove 16 which is machined into the guide control ring 12. The pitch of the groove 16 is preferably gradual as for example %1" to one revolution to aid in maintaining the blades in their set position. Each pivot shaft 14 is received within a counter bored well 17, half of which is cut into the retaining ring 11. A flange 18 on the bottom of the pivot shaft 14 retains the blade 13 within the well 17.

The blade shafts 14 are provided with a recess in the bottom thereof to receive therein a small disc of resilient material 19 such as a pad of rubber, leather, neoprene or the like. The shock pressure pad 19 serves to eliminate and absorb vibration of the propeller blade 13 and keeps the flange 18 in contact with the bearing surface of the well 17 provided by the shoulder 20 of the counter bored portion of the well 17.

The hub 10 is formed with a reduced, retaining ring receiving portion 21, best shown in Figure 3, and a reduced control ring retaining portion 22, formed on the outboard end of the hub 10. The interior of the hub 10 is provided with a two diameter bore 23, the reduced portion of which underlies the control 12. The reduced diameter of the bore 23 enables the control ring to be brought into conformity with the generally streamlined contour of the propeller hub which is desirable in marine structures. The portion of the hub 10 which underlies the control ring 12 is formed with two or more lugs 24, best shown in Figure 2, and which may be integral with the body of the hub 10. The outwardly extending lugs 24 slide through spaced tapered longitudinal slots 25 cut in the control ring 12.

When the control ring 12 is slipped upon the reduced portion 22 of the hub 10, the lugs 24 slide through the slots 25 until they extend beyond the face of the ring 12. Thereafter, the "ing is turned slightly until its shoulder 26 seats behind the lugs 24 which thereupon firmly lock it to the assembly. The tapered slots 25 are adapted to receive therein one or more brake blocks 27 and a pressure block 28. Brake blocks 27 substantially fill the tapered cavity formed by the control ring slots 25 and the outer surface of the hub 10'. These brake blocks 27 may be made of cork 34 preferably supported by a wedge of aluminum 35 or by an aluminum block having a layer of nylon, teflon or some other material attached thereto. The pressure block 28 is preferably made of rubber or other resilient material and serves to force the control ring 12 against the hub 10, squeezing the brake blocks therebetween.

It will be observed from an examination of Figures 2 and 4, that the hub 10 is not circular in cross-section but rather is pitched to provide a supporting bearing surface 29 for the leading edge of the propeller blade. In the embodiment illustrated the propeller is provided with three blades, each of which have a bearing surface 29, best shown in Figure l.

The control ring 12, with the detent 15 slipped into the slot 16 thereof, is brought over the outboard end of the hub and rotated to lock it in place upon the lugs 24. With the blades 13 in the position shown in Figure 4 within the hub 10, the retaining ring 11 is slipped over the hub 14} and brought against the blade pivot shafts 17. The retaining ring may be secured .to the hub 10 by means of screws and the threaded bores 30 provided in the hub 10 for this purpose. The propeller shaft nut 31 shown in dashed lines in Figures 1 and 3, may be secured to the streamlined appearance of the propeller;

When it is desired to vary the pitch of the blades 13 it is merely necessary to grasp the control ring 12 by means of the finger receiving portions 32 and rotate it slightly until the blades 13 have been swung about'their pivot shafts 14 by the travel of the detents 15 within the helical slot 16. The exact setting of the blades may be selected in advance by means of reference lines 33 which are scribed upon the hub and the ring 12. Once set, the propeller will remain in its position and operate without change therefrom despite conditions of vibration and the thrust of the water against the blades, because of the gradual incline of the helix of the grooves 16.

From the foregoing it will be seen that there has been disclosed a variable pitch propeller for marine use which is simple in construction 'and capable of retaining its adjustment despite prolonged periods of use.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

1'. An adjustable variable pitch propeller comprising, ahub, a retaining ring on said hub, a control ring rotatably carried onthe said hub, blade members pivotally secured at one end by the hub and extending outwardly therefrom, a helioal groove in the control ring, a guide detent depending'from the trailing edge of each of the blades and slidably received within the groove, brake means to yieldably hold the control ring at any desired setting upon the hub and means to override the brake means and rotate the control ring groove past the guide detents to vary the pitch of the blades.

' 2. Anyadjustable variable pitch propeller comprising, a hub, a retaining ring on one end of said hub, a control ring rotatably carried on the end of said hub opposite the retaining ring, blade members pivotally secured at one end by the hub and retaining ring and extending outwardly therefrom, a helical groove in the control ring, a guide detent depending from the trailing edge of each of the blades and slidably received within the groove, brake means to yieldably hold the control ring at any desired setting upon the hub and means to override the brake means and rotate the control ring groove past the guide detents to vary the pitch of the blades.

3. An adjustable variable pitch propeller comprising, a hub, -a retaining ring on said hub, a control ring rotatably carried on said hub, blade members, a pivot shaft extending from the base of each blade andpivotally secured at one end by the hub and extending outwardly therefrom, a helical groove in the control ring, .a guide detent depending from the trailing edge of each of the blades and slidably received within the grooves, brake means to yieldably hold the control ring at any desired setting upon the hub :and means to override the brake means and rotate the control ring groove past the guide detents to vary the pitch of the blades. i V

4. An adjustable variable pitch propeller comprising, a hub, a retaining ring on said hub, a control ring rotatably carried on the said hub, blade members pivotally secured at one end by the hub and extending outwardly theretrom, a plurality of helical grooves in the control ring, :1

. j 4 7 guide detent depending from the trailing edge of each of the blades and slidably received within each of the grooves, brake means to yieldably hold the control ring at any desired setting upon the hub and means to override the brake means and rotate the control ring grooves past the guide detents to vary the pitch of the blades.

5. An adjustable variable pitch propeller comprising, a hub, a retaining ring adjacent to the hub at the inboard end thereof, a rotatable controlring carried upon the outboard end of said hub, at least two openings in said hub and retaining ring formed by complementary cavities in the said hub and ring, a blade pivot shaft journaled within each opening, a blade on each shaft extending outwardly from said hub, a guide detent depending from the trailing edge of each blade, a helical-groove in the control ring to slidably receive the detent and means including the rotatable, {grooved control ring and the guide detents to simultaneously swing the blades to vary the pitch of the propeller. e

6. An adjustable variablepitch propeller comprising, a hub, a retaining ring adjacent to the hub at the inboard end thereof, a rotatable controlring carried upon the outboard end of said hub, at least two tapered longitudinal slots in the control ring, outwardly extending lugs on the outboard end of the hub receivable within the slots and extending therebeyond, at least two openings in said hub and retaining ring formed by complementary cavities in the said hub and ring, a blade pivot shaft journaled within each opening, a blade on each shaft extending outwardly from said hub, a guide detent depending from the trailing edge of each blade, a helical groove in the control ring to slidably receive the detent and means including the rotatable, grooved control ring and the guide detents to simultaneously swing the blades to vary the pitch of the propeller. I

7. An adjustable variable pitch propeller comprising, a hub, a retaining ring adjacent to the hub at the inboard end thereof, a rotatable control ring carried upon the outboard end of said hub, at least two tapered longitudinal slots in the control ring, outwardly extending lugs on the outboard end of the hub receivable within the slots and extending therebeyond, brake members consisting of resilient blocks carried within the s'lots and in contact with the hub, at least two openings in said hub and retaining ring formed by complementary cavities in the said hub and ring, a blade pivot shaft journaled within each opening, a blade on each shaft extending outwardly from said hub, a guide detent depending from the trailing edge of each blade, a helical groove in the control ring to slidably receive the detent and means including the rotatable, grooved control ring and the guide detents to simultaneously swing the blades to vary the pitch of the propeller.

References Cited in the file of this patent UNITED STATES PATENTS Thomas May 6, 1941 

